Motor vehicle window assemblies often have one or more sliders or sliding window panes, that is, window panes which slide either substantially horizontally or vertically with respect to the remainder of the window assembly. These sliding window panes can be either manually operated using a handle or power operated using an electric motor. Such window assemblies are used, for example, as rear windows for pick-up trucks and the like. Typically, one or more sliding window panes are mounted between fixed window panes in a frame. The frame typically integrates the sliding window panes and the fixed window panes as a self-contained pre-assembled module suitable for shipping and handling during installation into a motor vehicle.
As the desire for exterior surfaces of motor vehicles, including pickup trucks and the like, to be smoother and more aerodynamic has grown, a need has developed for window assemblies to present a more flush appearance. Typical rear window assemblies for pick-up trucks and the like have a central sliding window pane which is not flush with side fixed window panes. Rather, the sliding window pane is recessed from the fixed window panes in a direction toward the passenger compartment so that it can slide laterally inside one or both of the fixed window panes. Therefore, the window assembly does not contribute to a desired smooth exterior surface.
In order to contribute to a smooth exterior surface, window assemblies were developed having flush mounted sliding window panes. For example, see U.S. Pat. No. 4,850,139, the disclosure of which is expressly incorporated herein in its entirety by reference, which discloses a flush glass sliding window. The sliding pane is located in a slot having a wider portion so that the one side of the sliding pane can be manually pulled out of its flush closed position and thin slid inside the adjacent fixed pane. However, the window pane is free to shift and rattle in the wider slot when left in a closed unlocked condition. It is undesirable to have sliding window panes which are free to shift and rattle in such fashion.
In order to eliminate such rattling, window assemblies were developed having flush mounted sliding window panes that are constrained at all times. For example, see U.S. Pat. No. 5,542,214, the disclosure of which is expressly incorporated herein in its entirety by reference, which discloses a flush-closing multi-pane window assembly. The window assembly includes kick out means mounted on the frame which engage pins fixed to the sliding pane to force the sliding pane from its flush closed position to an offset parallel plane during initial lateral movement. However, the number of components and the relative mechanical complexity of this assembly makes it relatively expensive to produce. There is a never ending desire in the motor vehicle industry to reduce cost and weight.
U.S. Pat. Nos. 5,799,444 and 5,996,284, the disclosures of which are expressly incorporated herein in their entireties by reference, disclose a window assembly having a flush sliding pane. A pivoting handle is secured to the sliding window which slides along a channel. The handle has a cam projection in the channel so that the sliding window moves generally perpendicular to the window opening when the handle is rotated in one end of the channel. However, these window assemblies do not provide desired sealing performance. Accordingly, there is a need in the art for an improved window assembly having a flush sliding window pane.